"""
IModelStorage - Interface for model file storage.

Defines the contract for storing and retrieving model files (TensorRT, PyTorch, etc.)
"""

from abc import ABC, abstractmethod
from typing import Optional, BinaryIO
from pathlib import Path
import io


class IModelStorage(ABC):
    """
    Interface for model file storage.

    This abstraction allows swapping storage backends (local filesystem, S3, etc.)
    without changing the model conversion and loading logic.
    """

    @abstractmethod
    def write(self, key: str, data: bytes) -> None:
        """
        Write data to storage with the given key.

        Args:
            key: Storage key (e.g., "trt/hash123.trt" or "pt/hash456.pt")
            data: Binary data to write

        Raises:
            IOError: If write operation fails
        """
        pass

    @abstractmethod
    def read(self, key: str) -> Optional[bytes]:
        """
        Read data from storage by key.

        Args:
            key: Storage key

        Returns:
            Binary data if found, None otherwise

        Raises:
            IOError: If read operation fails
        """
        pass

    @abstractmethod
    def exists(self, key: str) -> bool:
        """
        Check if a key exists in storage.

        Args:
            key: Storage key

        Returns:
            True if key exists, False otherwise
        """
        pass

    @abstractmethod
    def delete(self, key: str) -> bool:
        """
        Delete data from storage.

        Args:
            key: Storage key

        Returns:
            True if deleted successfully, False if key didn't exist
        """
        pass

    @abstractmethod
    def get_local_path(self, key: str) -> Optional[str]:
        """
        Get a local filesystem path for the key.

        For local storage, this returns the direct path.
        For remote storage (S3), this may download to a temp location or return None.

        Args:
            key: Storage key

        Returns:
            Local path if available/downloaded, None if not supported
        """
        pass